OK .. I guess you don't have to sign up..
Alright so I listenned to the clip.
Nice clip.
Ok I see what you mean with the ringing.
Either your tubes are tired or you're driving your preamp too hard.
That's my take on it.
Is that amp equipped with a spring reverb?
If it is, then the preamp level may be a bit high for the tank.
There's also a very rich coating of reverb on the tune, could it be the interaction of the strings buzzing on the neck a bit blended with the spring verb then prounounced by the overall verb ?
Tristan